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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <h1>Late-load an animated gif and provide a pause button</h1>

<p>Improves initial page-load performance, and helps meet <abbr title="Web Content Accessibility Guidelines">WCAG</abbr> 2 level AA.</p>

<div class=container>
  <img class=img
       alt="Week 1 Challenge - Battenberg Cake">

<p>Initially load a static image (.jpg) then once the page has fully loaded, swap it out for the (much) larger animated gif.</p>
<p>A pause control is added which flips between the static image and the animation to meet WCAG 2 level AA. Which states a pause control is a requirement on animations which last longer than 5 seconds.</p>
<p>The animated gif is preloaded into memory then displayed preventing flashes of white occuring.</p>

<p>Sent for accessibility testing to the <a href="http://digitalaccessibilitycentre.org/">Digital Accessibility Centre</a>. Tested as fully compliant 23/09/2016.</p>

<p>Code repo available on <a href="https://github.com/2kool2/GIF-pause">GitHub</a>.</p>

<p class=smaller><a href="https://codepen.io/2kool2">Pens by Mike Foskett</a> &mdash; <a href="https://websemantics.uk/">webSemantics</a></p>

<svg style="display:none">
    <symbol viewBox="0 0 34 34" id="icon-play">
      <path d="M25 17.2l-14 7v-14l14 7z"></path>
    <symbol viewBox="0 0 34 34" id="icon-pause">
      <path d="M20 11h2v12h-2V11zm-8 0h2v12h-2V11z"></path>
              /* template override only */
button:focus {
  background-color: transparent;

/* Gif control */
.container {
.img {
  display: block;
  width: 100%;
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(1px, 1px, 1px, 1px);
.btn-anim {
  position: absolute;
  width: 36px;
  height: 36px;
  bottom: 12px;
  right: 12px;
  overflow: visible;

  cursor: pointer;
  padding: 0;
  border: 0 solid #fff;
  border-radius: 100%;

  /* IE10 - transparent background not allowed */
  background-color: rgba(255,255,255,.1);
.btn-anim:focus {
  outline: 0 solid;

.svg-pausePlay {
  pointer-events: none;
  width: 36px;
  height: 36px;
  border-radius: 100%;
  xxxoverflow: hidden;
  color: blue;
  background-color: #fff;
  fill: currentColor;
  -webkit-transition: all .3s ease-out;
  transition: all .3s ease-out;
.btn-anim:hover .svg-pausePlay,
.btn-anim:focus .svg-pausePlay {
  color: red;
  box-shadow: 0 0 0 4px red;
              var Gif_Load_Control = (function (window, d) {

    "use strict";

    // Wait until load event fires then go fetch large gifs.
    // On gif load replace the static jpg and add a pause button.
    // v1.2  - 27/09/2016
    //    To optimise verbalisation:
    //    Replaced ARIA and SVG titles with visually hidden text. 

    var dataAttr = "data-gif";

    var btnClass = "btn-anim";
    var btnOnClass = "btn-anim-on";

    var svgPlayIcon = "icon-play";
    var svgPauseIcon = "icon-pause";
    var svgClass = "svg-pausePlay";

    var txtPlay = "Play animation";
    var txtPause = "Pause animation";

    var _getSVG = function (icon, clss) {

        var svg = d.createElementNS("http://www.w3.org/2000/svg", "svg");

        svg.setAttribute("class", clss); // IE9 and Edge supported

        // Prevent IE focusing on SVG
        svg.setAttribute("focusable", "false");

        // Prevent "Graphic" from being spoken aloud by screen-reader
        svg.setAttribute("role", "presentational");

        var use = d.createElementNS("http://www.w3.org/2000/svg", "use");
        use.setAttributeNS("http://www.w3.org/1999/xlink", "href", "#" + icon);
        return svg;
    var _getSpan = function (txt, clss) {
        var span = d.createElement("span");
        span.setAttribute("class", clss); // IE9 and Edge supported
        span.textContent = txt;
        return span;

    var _displayImage = function (newImg, origImg) {

        // Comment out requestAnimationFrame for IE9 support
        window.requestAnimationFrame(function () {
            origImg.src = newImg.src;


    var _toggleAnimation = function (e) {

        var target = e.target;
        var origImg = e.target.origImg;

        // Comment out requestAnimationFrame for IE9 support
        window.requestAnimationFrame(function () {

            if (origImg.src === origImg.staticSrc) {

                origImg.src = origImg.animatedSrc;
                // IE9+ support
                target.setAttribute("class", target.className + " " + btnOnClass);
                target.textContent = "";
                target.appendChild(_getSVG(svgPauseIcon, svgClass));
                target.appendChild(_getSpan(txtPause, "visually-hidden"));

            } else {

                origImg.src = origImg.staticSrc;

                // IE9+ support
                target.setAttribute("class", target.className.replace(" " + btnOnClass, ""));

                target.textContent = "";
                target.appendChild(_getSVG(svgPlayIcon, svgClass));
                target.appendChild(_getSpan(txtPlay, "visually-hidden"));

    var _addPauseBtn = function (origImg) {

        var parentObj = origImg.parentElement;
        var btn = d.createElement("button");

        btn.origImg = origImg;
        // IE9+ support
        btn.setAttribute("class", btnClass + " " + btnOnClass);
        // Some screen-readers have issue reading the SVG title - don't use.
        btn.appendChild(_getSVG(svgPauseIcon, svgClass));

        // An aria-title doesn't work in all scenarios - don't use.
        // Instead use a visually-hidden span to contain play/pause text
        btn.appendChild(_getSpan(txtPause, "visually-hidden"));

        btn.addEventListener("click", _toggleAnimation, false);


    var _requestImage = function (src, origImg) {

        var newImg = new Image();

        origImg.staticSrc = origImg.src;
        origImg.animatedSrc = src;

        newImg.addEventListener("load", function () {

            _displayImage(newImg, origImg);

        }, false);

        newImg.src = src;

    var initialise = function () {

        var imgs = d.querySelectorAll("[" + dataAttr + "]");
        var i = imgs.length;
        while (i--) {
            _requestImage(imgs[i].getAttribute(dataAttr), imgs[i]);

    // Just run initialise() if this script is post-loaded.
    window.addEventListener("load", initialise, false);

}(window, document));

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